One of the equations of gravity is this:

Where v = final velocity which is 7m/s
u = initial velocity which is 0 for objects falling from a height
g = acceleration due to gravity and it is approximately 10m/s^2. It's a constant so pretty much remember this number. It's positive since the work being done is caused by gravity (in other words, it's falling down). It can also be negative if the work being down is against gravity (in other words, it's going up)
h = height of object
Substitute for the values and you should have something like this



Some of the most common examples of mechanical waves are water waves, sound waves, and seismic waves. There are three types of mechanical waves: transverse waves, longitudinal waves, and surface waves.
Erosion, weathering, mechanical changes, chemical changes.
Really, any interaction can change the composition of a rock whether it be done by man or through nature.
a) 32 kg m/s
Assuming the spring is initially at rest, the total momentum of the system before the collision is given only by the momentum of the bowling ball:

The ball bounces off at the same speed had before, but the new velocity has a negative sign (since the direction is opposite to the initial direction). So, the new momentum of the ball is:

The final momentum after the collision is the sum of the momenta of the ball and off the spring:

where
is the momentum of the spring. For the conservation of momentum,

b) -32 kg m/s
The change in momentum of bowling ball is given by the difference between its final momentum and initial momentum:

c) 64 N
The change in momentum is equal to the product between the average force and the time of the interaction:

Since we know
, we can find the magnitude of the force:

The negative sign simply means that the direction of the force is opposite to the initial direction of the ball.
d) The force calculated in the previous step (64 N) is larger than the force of 32 N.
Answer:
height of a cliff is 45.86 m
Explanation:
u=8 m/s
t=2.35 s
the height of the cliff is
